1a )When 50.0 mL of 0.500 M HCl at 25.0°C is added to 50.0 mL of0.500 M NaOH at 25.0°C in a coffee cup calorimeter, the temperatureof the mixture rises to 28.2°C. What is the enthalpy of reactionper mole of acid? Assume the mixture has a specific heat capacityof 4.18 J/(g ? K) and that the densities of the reactant solutionsare both 1.00 g/mL.
1b) Consider the following reaction: 2 PbS (s) + 3 O2 (g) ? 2PbO (s) + 2 SO2 (g) ?H = -827.4 kJ How many grams of PbS havereacted if 975 kJ of heat is produced? 1c) Consider the followingreaction carried out under constant pressure 3MgO(s) + 2NH3(g) ?3H2O(l) + Mg3N2(aq) ? Hrxn = 5.78×102 kJ Calculate the heatassociated with the complete reaction of 46.0 g of MgO with 17.1 gof NH3.
